Spinel,Stone,Facts,and,Informa education Spinel Stone Facts and Information
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Spinel is a special gemstone in many ways. For centuries the gem was mistaken for ruby and gained undeserved fame. The name spinel is either comes from the Latin word for thorn or the Greek spark. Although commonly thought of as red, this stone can be found in a range of outstanding pastel shades. These beautiful shades of blue, orange, purple, pink plus every combination in between make spinels one of the most desirable gemstones in the world. The most outstanding color is sapphire-like blue or ruby-like red. The coloring agents in spinel are chromium, iron, vanadium and cobalt. Red spinel intensifies its red color strongly under UV-light. Blue spinel weakens and turns reddish, green. The stone also comes in beautiful blues (which are also known as cobalt spinel), but those are very rare. Large stones and star spinels are also very rare.Because of its high clarity and excellent hardness (8 on Mohs scale), spinel is a very fine gem for all kinds of jewelry. Fine spinels are transparent and they are most sought after. Opaque spinel can sometimes display a star effect when cut as cabochon and it is a valuable rarity. Some large and famous rubies, such as the Timur Ruby and the Black Princes Ruby in the British Crown Jewels are actually spinels (until the beginning of the 19th century these red spinels were thought to be rubies).It's not surprising that spinel and ruby were long confused. Both of them are mined in the gem gravels of Sri Lanka and Burma. Spinel occurs with sapphire and ruby mainly in important deposits found in Myanmar, Cambodia, Thailand and Sri Lanka. Other locations are in Afghanistan, Brazil, Madagascar, Nepal, Australia, Tadzhikistan, Nigeria, Tanzania and the United States. Within the spinel group some trade names have become common:Balas spinel: Pale red spinelFlame spinel: Bright orange to orange-red spinelGahnospinel: Blue to dark blue or green spinelGrahnite: Blue, violet, or dark green to blackish spinelHercynite: Dark green to black spinelPicotite: Brownish, dark green, or blackish spinelPleonaste: Dark green to blackish, opaque spinel
Spinel,Stone,Facts,and,Informa